1. Field of the Invention
The present invention relates to a rotary drum filter having a drum which is rotatable around a substantially horizontal axis and having a filter cake cleaning-off unit, which drum and which cleaning-off unit are located inside of a filter housing that includes a raw air inlet, a clean air outlet and a filter cake discharge section, whereby the raw air inlet faces the outer jacket surface of the drum and the clean air outlet faces the inner jacket surface of the drum.
2. Description of the Prior Art
Such a rotary drum filter is generally known, and its filter cake cleaning-off unit operates with pressurized air in order to detach or remove, respectively, the filter cake from the outer jacket surface of the drum. Accordingly, the jet of pressurized air is directed in the mentioned rotary drum filter design from within the drum towards the inner jacket surface of the drum, flows therethrough and throws the filter cake located on the outer jacket surface of the drum off towards the outside. Known rotary drum filters of the above mentioned design incorporate the drawback that due to the impact of the pressurized air the filter removed from the drum does not fall downwards in a compact state, but rather dust thereof is raised, which again reaches the outer jacket surface of the drum. Accordingly, the air-flows within the housing of the filter are responsible for such happening, which air-flows prevent a compact setting of the dust in a settling space (bin, container, trough) for such dust.